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Matching into emergency medicine (EM) is getting progressively more competitive. Applicants must therefore prepare for the possibility of not matching and, accordingly, be ready to participate in the Supplemental Offer and Acceptance Program (SOAP). In this article, we elaborate on the SOAP and the options for applicants who fail to match during Match Week. Alternative courses of action include applying for a preliminary year, matching into a categorical residency program, or aiming to secure EM spots outside the Match through the Council of Emergency Medicine Residency Directors, Society for Academic Emergency Medicine, and American Association of Medical Colleges.

Among many iron-based superconductors, isovalently substituted BaFe2(As1−xPx)2 displays, for x ≈ 0.3, apart from the quite usual Second Magnetization Peak (SMP) in the field dependence of the critical current density, an unusual peak effect in the temperature dependence of the critical current density in the constant field, which is related to the rhombic-to-square (RST) structural transition of the Bragg vortex glass (BVG). By using multi-harmonic AC susceptibility investigations in three different cooling regimes—field cooling, zero-field cooling, and field cooling with measurements during warming up—we have discovered the existence of a temperature region in which there is a pronounced magnetic memory effect, which we attributed to the direction of the structural transition. The observed huge differences in the third harmonic susceptibility at low and high AC frequencies indicates the difference in the time-scale of the structural transition in comparison with the timescale of the vortex excitations. Our findings show that the RST influence on the vortex dynamics goes beyond the previously observed influence on the onset of the SMP. [ABSTRACT FROM AUTHOR]

Featured Application: This work concerns the study of the granular nature of an YBa2Cu3O7-x superconducting film, whose expertise can be useful in understanding the temperature and the DC and AC field application ranges of these materials with non-optimized fabrication properties, which are typically found in superconducting wires and power cables. The study of granularity in superconducting films by using AC susceptibility has a crucial role in the development of and improvement in the ReBCO-coated conductors, which are a constantly evolving reality in the modern power applications of superconductivity. Specifically, the study of the granularity is essential because the ReBCO superconducting wires and tapes are far from the regularity of a single crystal while they often present an inter- and intragranular contribution to the critical current density. On the other hand, the AC susceptibility is a key part of the characterization of a granular sample because this technique is very sensitive to the presence of granularity in the superconductors and, moreover, the study of its first harmonic allows for determining pivotal properties such as the pinning energy as well as the dissipation processes acting in the sample. The pinning energy values and the granularity of an YBCO thin film have been studied by means of AC susceptibility measurements as a function of the AC amplitude, temperature, and DC field. In particular, the first harmonic imaginary component of the AC susceptibility χ 1 ″ related to the dissipation processes of the sample has been studied. First, starting from the Brandt approach, the critical current density Jc and the pinning energy U of the sample have been extracted at 77 K by using the χ 1 ″ measurements as a function of the AC amplitude at different AC frequencies and DC fields. From these measurements, a first signal of granularity appears. In order to confirm it, the temperature dependence of the χ 1 ″ at different DC fields has been studied and a contribution deriving from the inter- and intragranular part of the sample has emerged. By taking the temperature corresponding to the crossover between the two contributions at the different DC fields, the intergranular and intragranular response has been separated. Successively, the temperature has been fixed to 77 K, together with an AC frequency equal to 1597.9 Hz, and the χ 1 ″ as a function of the DC field at different AC amplitudes has been analyzed showing a clear presence of granularity in all the curves. By drawing the contour plot of the χ 1 ″ with the DC and AC values, it was possible to determine the best parameters to put at 77 K in order to exploit the material for applications. [ABSTRACT FROM AUTHOR]

We report on the effects of 3.5 MeV proton irradiation in RbCa2Fe4As4F2, an iron-based superconductor with unusual properties in between those of the pnictides and of the cuprate high-temperature superconductors. We studied how structural disorder introduced by ion bombardment affects the critical temperature, superfluid density and gap values by combining a coplanar waveguide resonator technique, electric transport measurements and point- contact Andreev-reflection spectroscopy. We find an unusually weak dependence of the superconducting properties on the amount of disorder in this material when compared to other iron-based superconductors under comparable irradiation conditions. The nodal multigap state exhibited by pristine RbCa2Fe4As4F2 is also robust against proton irradiation, with a two- band d-d model being the one that best fits the experimental data. [ABSTRACT FROM AUTHOR]

The effect of the demagnetizing factor, regarding the determination of the de-pairing current density J d e p , has been studied in the case of a Fe(Se,Te) crystal, using DC magnetic measurements as a function of a magnetic field (H) at different temperatures (T). First, the lower critical field H c 1 (T) values were obtained, and the demagnetization effects acting on them were investigated after calculating the demagnetizing factor. The temperature behaviors of both the original H c 1 values and the ones obtained after considering the demagnetization effects ( H c 1 d e m a g ) were analyzed, and the temperature dependence of the London penetration depth λ L (T) was obtained in both cases. In particular, the λ L (T) curves were fitted with a power law dependence, indicating the presence of low-energy quasiparticle excitations. Furthermore, by plotting λ L − 2 as a function of T, we found that our sample behaves as a multigap superconductor, which is similar to other Fe-11 family iron-based compounds. After that, the coherence length ξ values were extracted, starting with the H c 2 (T) curve. The knowledge of λ L and ξ allowed us to determine the J d e p values and to observe how they are influenced by the demagnetizing factor. [ABSTRACT FROM AUTHOR]

This correction notice addresses an error in the original publication of a scientific article titled "Pinning Energy and Evidence of Granularity in the AC Susceptibility of an YBa2Cu3O7-x Superconducting Film." The error pertains to the sample thickness, which was incorrectly stated as 50 μm instead of the correct value of 4 μm. The correction has been made to the relevant sections of the article, including the results and discussion. The authors assure that this correction does not impact the scientific conclusions of the study. [Extracted from the article]

For practical applications of superconductors, understanding the vortex matter and dynamics is of paramount importance. An important issue in this context is the transition of the vortex glass, which is a true superconducting phase, into a vortex liquid phase having a linear dissipation. By using multi-harmonic susceptibility studies, we have investigated the vortex glass—vortex liquid phase transitions in CaKFe4As4 and BaFe2(As0.68P0.32)2 single crystals. The principle of our method relates the on-set of the third-harmonic susceptibility response with the appearance of a vortex-glass phase in which the dissipation is non-linear. Similar to the high-critical temperature cuprate superconductors, we have shown that even in these iron-based superconductors with significant lower critical temperatures, such phase transition can be treated as a melting in the sense of Lindemann's approach, considering an anisotropic Ginzburg-Landau model. The experimental data are consistent with a temperature-dependent London penetration depth given by a 3D XY fluctuations model. The fitting parameters allowed us to extrapolate the vortex melting lines down to the temperature of liquid hydrogen, and such extrapolation showed that CaKFe4As4 is a very promising superconducting material for high field applications in liquid hydrogen, with a melting field at 20 K of the order of 100 T. [ABSTRACT FROM AUTHOR]

We present the multifrequency measurements of the surface resistance of spark-plasma-sintered MgB 2 performed through a dielectric loaded resonator operating at 16.5 and 26.7 GHz. By normally applying magnetic fields ≤1.2 T to the sample surface, we drove it in the mixed state. By means of data-rooted analysis, we found that the sample vortex dynamics could be fully described within a single-component approach. Pinning phenomena were present and characterized by a depinning frequency smaller than the measurement ones. The multiband nature of the superconductor emerged in the flux-flow resistivity, whose field dependence could be interpreted well within theoretical models. By exploiting them, the upper critical field was extracted in the low-temperature range, which exhibited a consistent temperature trend with the values obtained at the onset of the resistive transition near T c , and was well in line with literature data on other polycrystalline samples. [ABSTRACT FROM AUTHOR]

Background: The subendocardial viability ratio (SEVR), also known as the Buckberg index, is a parameter of arterial stiffness with indirect prognostic value in assessing long-term cardiovascular risk. Materials and Methods: We conducted a prospective cohort study on 70 patients with uncomplicated hypertension admitted to a county medical reference hospital. We analyzed demographics, laboratory data, arterial stiffness parameters and cardiovascular risk scores (SCORE and Framingham risk scores) and aimed to identify paraclinical parameters associated with increased cardiovascular risk. Results: Of the arterial stiffness parameters, SEVR correlates statistically significantly with age, central and peripheral systolic blood pressure, as well as with heart rate. SEVR seems to have prognostic value among hypertensive patients by increasing the risk of major cardiovascular events assessed by SCORE and Framingham risk scores. SEVR correlates statistically significantly with serum fibrinogen (p = 0.02) and hemoglobin (p = 0.046). Between pulse wave velocity and lipid parameters (p = 0.021 for low-density lipoprotein cholesterol and p = 0.030 for triglycerides) a statistically significant relationship was found for the study group. The augmentation index of the aorta also correlated with serum LDL-cholesterol (p = 0.032) and the hemoglobin levels (p = 0.040) of hypertensive patients. Conclusions: Age, abdominal circumference and Framingham score are independent predictors for SEVR in our study group, further highlighting the need for early therapeutic measures to control risk factors in this category of patients. [ABSTRACT FROM AUTHOR]

Reporting on a straightforward and cheap method for creating strong pinning centers in SC films by growing three-dimensional nanodots on the substrate prior to SC films by deposition is presented. Suggesting that our method can be used for the reduction of thermal noise in high-T (sub c) dc SQUID's.

For high-field power applications of high-temperature superconductors, it became obvious in recent years that nano-engineered artificial pinning centers are needed for increasing the critical current and pinning potential. As opposed to the artificial pinning centers obtained by irradiation with various particles, which is a quite expensive approach, we have studied superconducting samples having self-assembled defects, created during the sample fabrication, that act as effective pinning centers. We introduced a simple, straight-forward method of estimating the frequency-dependent critical current density by using frequency-dependent AC susceptibility measurements, in fixed temperatures and DC magnetic fields, from the positions of the maxima in the dependence of the out-of-phase susceptibility on the amplitude of AC excitation magnetic field. The results are compatible with a model that stipulates a logarithmic dependence of the pinning potential on the probing current. A mathematical derivation allowed us to estimate from the experimental data the pinning potentials in various samples, and in various DC magnetic fields. The resulted values indicate large pinning potentials, leading to very small probability of magnetic flux escaping the pinning wells, hence, leading to very high critical currents in high magnetic fields. [ABSTRACT FROM AUTHOR]

The deposition of a ferromagnetic layer can affect the properties of high-temperature superconductors underneath. We investigated the influence of ferromagnetic CaRuO3 on the properties of YBa2Cu3O7-x (YBCO) superconducting thin films when the layers are either in direct contact or separated by a barrier layer of 5 nm SrTiO3. Detailed measurements of the magnetic moment of the superconductor and ferromagnet as a function of temperature and magnetic field have been performed using SQUID magnetometry. Magnetometry and relaxation measurements show that the modification of the superconducting properties of YBCO strongly depends on the interaction with the ferromagnetic layer on top. The barrier layer has a significant impact on both the supercon-ducting properties of the YBCO film and the ferromagnetic ordering of CaRuO3. The physical properties mentioned above were discussed in correlation with the materials' structure determined by XRD analysis. [ABSTRACT FROM AUTHOR]

This paper presents right helicoid surfaces in various systems of representation. Emphasis was put on the representation of helicoid surfaces in the projection with elevations, where both the right helicoid with a perpendicular axis on the elevated plan and the right helicoid with the axis inclined at a certain angle to the elevated plan. [ABSTRACT FROM AUTHOR]